Material: carbon steel, alloy steel or stainless steel Certificates: ISO9001-2008,GL,ABS Forged process: hot forged N or Q+T. Size:big size or customers requipment£» OD30mm¡ª250mm,LENGTH 3000mm¡ª-6000mm£»weight from 100 kg to 1000kg£» All Alloy steel, stainless steel,carbon steel